Mining machine



M. P. HOLMES MINING MACHINE Aug. 15, 1933.

Filed July 24, 1931 3 Sheets-Sheet l z f w .n w

WAM; AMW.

Aug. 15, 1933. M. P. HOLMES 1,922,293

MINING MACHINE .Filed July 24, 1931 3 Sheets-Sheet 3 /m/f/r 70H /VOHH/s P HOLMES.

E Awa /J www Patented Aug. l5, 1933` MINING MACHINE Morris P.,Holmes, Claremont, N. H., assigner to Sullivan Machinery Company, aCorporation ol?v Massachusetts Application July 24, 1931. Serial No. 552,936

49 laim's.

This invention relates to miningl machines and more particularly, but not exclusively, to improvements in the `feeding mechanism of a coal mining machine of the flexibly fed,` continuous cutter, bottom cutting type.

object, o-f this invention is to provide an improved coaly mining machine. Another object is. toprovide an improved mining `machine feeding mechanism. A further object is to provide izmtrovedV flexible feeding means `for a mining machine `ofthe continuous cutter, bottom cuttingtype.v Yet another object is to provide improved feeding mechanism particularly adapted for use in mining machines of the long-- 'wall type.` Still another `object is to provide an improved flexible` feeding means for a coal mining machine wherein a feed operating"memM ber cooperating `with a `lieiiible feeding element is employed having an improved plural speed transmission mechanism whereby the feed operating member is driven in an improved manner in a direction to draw. vin its cooperating flexible `feeding means.` at either a relatively low cutting speed or a relatively high 25. moving speed.` Yet another object isto `provide improved pluralspeed transmission mechanism for a ,mining machine feeding mechanism` `wherein a. comparatively small number of moving yparts arei employed and which is of extremely rugged and compact construction. These and. other objects ofV this invention will, l'iowever; hereinafter morefully appear in the course of the following description and as more particularly pointed out in the appended claims. i I Infthe accompanying drawings there is shown for ofY illustraticn'one form and inodiflcation y .ich the invention may assume in practice.; .l 1 i In; these drawings,- F,

40` Vi'gxl: is` a pian View of a longwall coal mining machine having embodied therein the illustrativoV form` `of the improved feeding mech- 2 is an enlarged horizontal sectional View taken. substantially on line 2--2 `of Figi. 3 and illustrating ther proved plural speed transmission mebhanz lin` and the associated control means.

Fig. 3 is a central longitudinally extending lineB-B of. Fig. 2. i

i is a detail vertical sectional view taken on line /l-fl oi Fig.` 2. i

5 is a transverse vertical sectional `View taken on line 5--5 of Fig. 2.

-zontal swinging movement about a vertical ll for guiding the feed cable relative to the vertical' sectional. View talren` substantiallg-T on' -ed rleirible feeding means is shown embodied in a coal mining machine of the continuous cutter, of bottom cutting, longwall type generally comprising a frame 1 having a plane bottom surface 2 and adapted to rest upon and slide overithe mine floor. Pivotally mounted at 3 for hori- I0 is a cutter bar e carrying on. its margin a usual endless cutter chain 5. As is usual `in mining machines of the type disclosed, the cutter bar is swingable into diierent angular positions relative to the machine frame and is adapted to be locked its diiferent positions by a rotary locking pin 6 carried by the cutter bar and engageable with notches 7 formed in the outer periphery of a flange 8 integral with the frame 1. The machine is fed over the fmine fioor at a relatively `low cutting speed and at relatively highmachine moving speed byv usual feed operating member, herein a haulage or cable Winding drum 9, arranged for rotation about a vertical 'axis and liaving'Wound thereupon a i ual ne feed cable 10. Arranged at'opnosite sides of the haulage `drum 9 are guide sheaves feed drum during the various operations of the machicle.` The feed cable connectible to the lock- 'ing pin in a usual manner, as indicated in dotted lines in ligh l, and when the locking pin is released, the feed cable may be Wound in by the haulage drum to effect swinging of the cutter bar about its pivot; During feeding of the machine along the coal face, the feed cable is extended from the haulage drum 9 in the manner indicated in full lines in Fig. l and is oonnccted `at its free end to a Asuitable anchor located in advance of the machine adjacent the coal face, and as the cable is `Wound in, the machine is ied bodily over the mine door in the manner Well understood in the art. The cutter chain 5 and the haulage drum 9 are driven by a motor 12, which may be of the reversible-electype, having its power shaft 13 horizontally` `disposed and extending longitudinally of the transmission mechanism between the motor power shaft and the haulage drum 9, it will be noted that keyed to the one end of the motor power shaft 13 is a spur pinion 14 meshing, as shown in Fig. 5, with an intermediate or idler gear 16. The gear 16 is suitably journaled on the stub shaft 17 mounted within the machine frame and meshes with a spur gear 18 keyed at 19 to a hollow transmission shaft 20. The shaft 20 is horizontally disposed and is arranged with its axis parallel with the power shaft axis, as shown in Fig. 2, and is journaled on a stationary shaft 21, the shaft 21 extending centrally through the hollow shaft 20 and fixed at its ends at 22 within the machine frame. Herein formed integral with the hollow shaft 20 is a worm 23, which is herein a fast speed worm, meshing with a fast speed worm wheel 24. Also meshing with the worm 23 is a worm wheel 25 fixed at 26 to a vertical shaft 27 arranged for rotation about a vertical axis. This shaft is herein made hollow and is journaled at its ends on stub shafts 28, 28 fixed within bores 29, 29 formed in the machine frame, the upper bore being formed in the detachable top plate of the frame housing the feeding mechanism. Keyed at 30 to the upper end of the shaft 27 is a spur gear 31 meshing with a spur gear 32 keyed at 33 to a vertical shaft 34 herein arranged parallel with the shaft 27 and in the same longitudinally extending Vertical plane. The shaft 34 is likewise made hollow and is journaled in aV similar manner on stub shafts 35, 36, the former being fixed within a bore 37 formed in the detachable top plate of machine frame, while the latter is formed integral with a detachable bearing retaining cap 38. Herein secured to the shaft 34 is a worm 39 which meshes with a worm wheel 40 keyed at 4l to a hollow shaft 42 herein alined with the shaft 20 and likewise journaled on the shaft 21. Formed integral with the shaft 42 is a worm 43, which herein constitutes the slow speed worm, meshing with a slow speed worm wheel 44. The worm wheels 24 and 44 are arranged in parallel relation on vertical axes lying in the central longitudinal vertical plane of the machine as shown in Fig. 2, and respectively drive through multiple disc clutches 45 and 46 and interlocking mechanisms 47 and 48 vertical shafts 49 and 50 respectively. The shafts 49 and 50 are herein arranged coaxial with the worm wheels 24 and 44 respectively, and have respectively secured thereto at their lower ends, and driven thereby, spur pinions 51 and 51a meshing with the teeth of an internal gear 52 herein formed integral with the haulage drum 9, as clearly shown in Fig. 3. As the means for journaling the worm wheels 24, 44 and shafts 49, 50 within the machine frame and the structure and control of the disc clutches and interlocking mechanisms are identical in design, the description of the structure of the drive and controlling elements coaxial with the worm Wheel 24 will sumce for both. rIhe worm wheel 24 has its upper and lower hubs journaled in bearing sleeves 53, 53 supported by a hollow shaft 54 surrounding the shaft 49 and suitably journaled within the machine frame. This worm wheel carries a series of clutch. discs 55 interleaved with a corresponding series of clutch discs 56 carried by the hollow shaft 54. Surrounding the shaft 54 adjacent its upper end is a clutch applying member 57 connected through an anti-friction bearing 53 to an annular clutch member 59 slidably mounted on the enlarged portion 66 of the shaft 54. When the clutch member 59 is moved downwardly from the position shown in Fig. 3, it engages plungers 61 and through these plungers transmits pressure to the discs of the friction clutch to frictionally connect the worm wheel 24 to the vertical shaft 54. The friction clutch 46 controlling the connection of the worm wheel 44 in driving relation with the haulage drum is provided with a similar clutch member 62 connected by an anti-friction bearing 63 to a clutch applying member 64. It will thus be seen that when the clutch 45 is applied and the clutch 46 released and the interlocking mechanism 47 is connected and the interlocking mechanism 48 is released, the haulage drum may be driven through the fast speed worm gearing 23, 24 in a direction to wind in its cooperating feed cable at a relatively high speed. When the clutch 46 is applied and the interlocking mechanism 48 connected, and the clutch 45 is released and the interlocking mechanism 47 disconnected, the haulage drum may be driven through the slow speed worm gearing 43, 44 at a relatively low speed.

Now referring to the interlocking mechanism 47, 48 for connecting the hollow shafts to the shafts 49, 50 respectively, it will be noted that each of the clutch elements 59, 62 is internally grooved at 65 and is provided with oppositely disposed cam surfaces 66 and 67. Projecting within the groove 65, when the latter is in the position shown in Fig. 3 are interlocking clutch plungers 68 slidably mounted within radial chambers 69 formed in the enlarged portion of' operating therewith shipper yckes 73 and 74, the

former fixed to an operating rod 75 and the latter to a hollow operating sleeve 76 arranged concentrically with and surrounding the rod. The rod and sleeve are suitably rotatably supported within the machine frame and secured as by a pin to the outer extremity of the rod is a toothed clutch element 77, while formed on the outer end of the sleeve are clutch teeth 73. Slidably mounted on the rod is an operating handle 79 having formed on the opposite sides of its hub, clutch teeth 80 and 81. A suitable spring pressed plunger lock S2 carried within the grasping portion'of the handle is provided for locking the handle in its different angular positions. The handle 79 constitutes the common operating element for the clutch shipper yokes and when the handle is in the position shown in Fig. 2 with the teeth 80 thereon connected to the teeth 78 formed on the sleeve the sleeve may be rotated while the rod remains stationary, and as a result, the interlocking mechanism 48 is connected and the clutch 46 applied, while 1 the interlocking mechanism 47 and the clutch 45 are released. When the handle 79 is moved outwardly to release the teeth thereon from the teeth on the sleeve and connect the teeth 81 with the teeth of the clutch element 77, the rod 75 may be turned while the sleeve remains stationary, and. as a result, the interlocking mechanism14'1` and clutch 45 may be connected while the other interlocking mechanism and clutch arer released.

When the parts are in the position, shown in Figs. 2 and 3, the clutch plungers 68y are. held within the annular recesses formed ini the `clutch elements 59 and 62` respectively with the inner ends of -the `clutch plungers wholly released from the groove. formed in the shafts 49 and 50. When the clutch members 59 and62 are in this position, the clutches 45 and 46 are both released. At this time, the haulage drum Qumay rotate freely relative to its drive mechanism, the shafts 49 and 50 upon rotation of the haulage drumy turning freely within the hollowV shafts 5.4L When` it is; desired to effect` drive of the haulage drum in winding directiony at a relatively low speed, that is ar speed suitable for effecting feed of the machine during the cutting operation, the clutch 62 is shifted upon suitable manipulation of the `operating handle 'I9l to` cause a cam `surface thereonV to force the clutch plungers 48 inwardly into interlocking `engagement `with the `grooves on, the shaftO,

thereby connecting the shaft 56 to its` hollow drive shaft 54. When the clutch member is further depressed, the plungers 61 are engaged and Y fore the provision of the interlocking mechanisms between the driving and driven shafts drag rotationwas imparted by the clutch `discs of the disc clutches, even when thelatter` were `in Vtheir released position, which caused the `haulage `drum to rotate. tions, for instance when the motor wasreversed,

it has been found that the drag in the clutchV Under certain condi- `discs, even when in their released position, was sufficient tof cause `the haulage drum to rotate to unwind the feed cable and somedanger of causing thelatter to becomedangled and `twist-` ed. i By the provision of the interlocking mechanisms betweenthc disc clutches and the `drive shafts, it is possible, when "the clutch` mechanisms are released, to relievev entirely the haulageidrum from action of the clutch discs, so that when the clutch operating meansrare in their Aneutral position, the `haulage drum remains stationary or may be freely manually rotated. This is an especiallydesirable feature rwhen itis desired to unwind the feed cable from` the haulage drum byhand.

p Inthe modildcation shown inFig. 7i, the spur pinion 14 meshes with spur gear 85 which has rotatable therewith drives a spur gear 83 meshing with` a spur 87. The latter gear is` fixed to a shaft 88 `herein parallel with the` motor shaft and` suitably journals-id within the lmachine fra-mc. `Herein formed integral with the shaft 88 is a spur pinion 89 meshing with a spur 90 keyed to a shaft 91 herein arranged parallel with the shaft 88, as illustrated. Keyed' to and driven by the shaft" 91 is vimproved plural speed drive and control.

`a spur pinion` 92 meshing with a spur gear "93% keyed to a horizontal shaft 94 hereinarranged in axial alinement with the shaft 88. Keyed to the shafts 88 and 94 are fast and slow speed worms 95 and 96 respectively which mesh rei.

spectively with the worm wheels 24 and` 44 described above. YThe connections between the worm wheels 24 and 44 and the haulage drum are identical to those described above. It will thus be seen that the worm wheel 24 may be driven at a high speed through the gear train 14, 85, 86, 87, shaft 88 and worm 95, while the slow speed worm wheel 44 maybe driventhrough the gear train 14, 85, 86, 87, 89, 90, 92 and 98. As the operation of this form of the mechanism is` the same as that in the form described above, further description of the same is thought unnecessary.

As thermode of use of a longwall coal mining MImachine ofthe typo disclosed herein is well understood to those skilled in the art, and as the operation of the improved plural speed transmission mechanism for driving the haulage drum. at relatively high andlow speeds has been clearly described above, a .detail description of the mode of operation of the machine is considered unnecessary.

As a result of this invention, it will be noted that animproved mining machine feeding mechanism is provided which is of an extremely rugged and compact characterl especially adapted to use in coal mining machines ofA the' longwall type wherein the spacial .dimensions are restricted to a minimum.` ltwill' further be noted that by arranging the fast and slow speed worm gear trains in the manner disclosed and driving'lthe feed drum by separate pinions' engaging the drum driving gear and driving the worm gearing through the connections described, it has been found possible to materially reduce the numberof moving parts while still retaining an The various uses' of the machine and various other advantages derived from this `invention will be clearly apparent to those skilled in the art. p

While I have in this application specifically described one form anda modification which the invention may assume iii-practice, it will be understood that this form and a modification are shown for purposes of illustration and that the member including afast speed gear train andY a slow speed gear train, each including a drive tudinal vertical center of the machine and both drive gears meshing with a gear common `to both and rotatablev with the feed operating member.

2. In a mining machine, the combination with a feed operating member adapted to cooperate directly'with flexible feeding means, of motor operated driving means for said feed operating lli() `gear rotating about an axis lying inthe longi- Y member including fastspeed transmission means ico tively locking the shafts thereof together or to permit free relative rotation therebetween.

3. In a mining machine, the combination with a feed operating member adapted to cooperate directly with flexible feeding means, of motor operated driving means for said member including a fast speed transmission means and a slow speed transmission means, each of said transmission means including, and having individual thereto, a releasable positive interlocking mechanism and an operator controlled controlling clutch.

4. In a mining machine, the combination with a feed operating member adapted to cooperate directly with flexible feeding means, of motor operated driving means for said member including a fast speed transmission means and a slow speed transmission means, each of said transmission means including, and having individual thereto, an operator controlled positive interlocking mechanism and an operator controlled controlling clutch.

5. In a mining machine, the combination with a feed operating member adapted to cooperate directly with flexible feeding means, of motor operated driving means for said member including a fast speed transmission means and a slow speed transmission means, each of said transmission means including, and having individual thereto, a shaft, a friction clutch for connecting said shaft to its drive, a driven shaft, and an operator controlled connecting device for locking said shafts together or for permitting free relative rotationV therebetween.

6. In a mining machine, the combination with a feed yoperating member disposed on a vertical axis and adapted to cooperate directly with flexible feeding means, of motor operated driving means for said member including a fast speed transmission means and a slow speed transmission means, eacn of said transmission mean including a driving element, a driven shaft, clutch means for connecting said shaft to said driving element and a gear fixed to said shaft, and said feed operating member having a gear rotatable therewith and with which the gears of said transmission means mesh.

7. In a mining machine, the combination with a feed operating member adapted to cooperate directly with flexible feeding means, of motor operated driving means for said member including a .fast speed gear train and a slow speed gear train, each of said gear trains including intermeshing worm gearing, yand the worm wheels of said gearing rotating about parallel axes lying in the longitudinal vertical center of the machine.

8. In a mining machine, the combination with a feed operating member disposed on a vertical axis and adapted to cooperate directly with flexible feeding means, of motor operated driving means for said member including a fast speed gear train and a slow speed gear train, each of said gear trains including intermeshing worm gearing, and the Worm wheels of said gearing rotating about parallel vertical axes.

9. In a mining machine, the combination with a feed operating member adapted to cooperate directly with flexible feeding means, of motor operated driving means for said member including a fast speed gear train and a slow speed gear train, each ci said gear trains including intermeshing worm gearing, and the worms of said gearings rotating on alined axes and the worm Wheels rotating about parallel axes and lying in the central longitudinal vertical plane of the machine.

10. In a mining machine, the combination with a feed operating member adapted to cooperate directly with flexible feeding means, of motor operated driving means for said member for driving the latter in a direction to draw in said flexible feeding means including relatively rotatable shafts arranged in axial alinement, fast and slow speed gears driven by said shafts respectively, gears meshing With said gears, and a gear rotatable with said feed operating member and driven by said last mentioned gears selectively.

l1. In a mining machine, the combination with a feed operating member adapted to cooperate directly with flexible feeding means, of motor operated drive means for said member including a fast speed transmission mechanism and a slow speed transmission mechanism, said transmission mechanisms including coaxial worms and Worm wheels meshing with said Worms respectively and rotating on axes parallel with the axis of said feed operating member.

l2. In a mining machine, the combination with a feed operating member adapted to cooperate directly with flexible feeding means, of motor operated drive means foi` said member including a fast speed transmission mechanism and a slow speed transmission mechanism, said transmission mechanisms including coaxial worms and worm wheels meshing with said worms respectively and rotatable about parallel axes parallel with the axis of said feed operating member. i

13. In a mining machine, the combination with a feed operating member adapted to coop- 'erate directly with flexible feeding means, of

motor operated drive means for said member including a fast speed transmission mechanism and a slow speed transmission mechanism, said transmission mechanisms including coaxial Worms and worm wheels meshing with said worms respectively and rotatable about parallel vertical axes parallel with the axis of said feed operating member.

1li. In a mining machine, the combination with a feed operating member adapted to coopcrate directlyv with flexible feeding means, of motor operated drive means for said member including a fast speed transmission mechanism and a slow speed transmission mechanism, said transmission mechanisms including coaxial Worms and worm wheels meshing with said worms respectively and rotatable about parallel verticalV axes lying in the central longitudinal vertical plane of the machine.

l5. In a mining machine feeding mechanism, a feed drum disposed on a vertical axis, an internal gear fixed to said drum, gears meshing with said internal gear, a fast speed driving mechanism for one of said latter gears, and a slow speed driving mechanism for said other latter gear.

16. In a mining machine feeding mechanism, a feed drum, and plural speed driving means for said drum including a fast speed gear train and a slow speed gear train, said fast speed gear train including a worm and a worm wheel driven thereby, and said slow speed gear train including a worm wheel also meshing with said worm. Y

1'7. In a mining machine feeding mechanism, a feed drum, and plural speed driving means for said drum including a fast speed gear train said drum, and driving connections betweenone and a slow speed-` gear train, said fast speed gear train including a worm and a worm wheel driven thereby `and said slow speed gearwtrain including. a worm Wheel meshing with said worm means for said drum including ,coaxial worms,

Worm Wheels meshing with said Worms respectively and each operatively connectible to drive said drum and Vdriving connections between ,one 0f said iworms and said othervvorm including an element meshing with one of said Worms."

A19. ,In amining machine feeding mechanism including a feed drum andplural speed `driving meansfor` said drum including coaxialworms, Worm Wheels meshing with said Worms 'respectively and each operatively connectible to drive saiddrum, andgdriving connections between one of `said Worms and said other Worm including a Worm wheel meshing ,with the wormof .the fastspeed' gearing.

,20. ,In a ,mining machine feedingfmechanism including a feed-drum and plural speed driving means for saiddrum including coaxial .Worms, worm wheelsmeshing with saidwormsrespectively and eachoperativelyconnectible to* drive said drum, and `driving connections betweenone of said Worms rand said other .Wormincluding a worm Wheel meshing with the Worm of the fast speed gearing, :and -a Worm rotating about an axis parallel to said last mentioned worm Wheel and a Worm Wheel meshing with said `last mentioned worm. e e A y21. Ina mining machine feeding mechanism V,including a feed drum and pluralspeed driving means for said-drum including coaxial Worms, Worm vvvheels meshing with said Worms respectively and eachioperatively connectible to drive of said Wormsand said other Worm including a Worm Wheel meshing With the Worm ofthe fast speed gearing, and a Worm rotating about an axis parallel to said last mentioned worm Wheel `and avvorm Wheel meshing `with saidlast men-` tioned lvvornr and Vrotating on an `axiscoaxial `Withand driving the Worm of saidslow speed `gear train. i

`22. In` a mining machine, the combination with a feed operating memberadapted to "cooperate directlyI withiiexible ,feeding means, of; motor operated driving means jfor said .feed

operating member `including a fast speed transmission mechanism vand a slow `speed transmission mechanism, `said `transmission mechanisms including coaxial Worms relatively rotatable at different speeds, and worm Wheels meshing with said Worms respectively and selectively operatively connectible to said feedoperating member.

23. In a mining machine, lthe combination ".With a feed operatingmember Yadaptedto cooperatedirectly with `flexible .feeding means, of

motor operatedidriving means for said feed oper- "ating memberfincludinga fast speed transmisoperate directly with flexible feeding means, of

motor operated driving means for said feed operating member including a fast speed transmission mechanism anda slow speed transmission mechanism, said transmission mechanisms including coaxial worms relatively rotatable ,at different speeds, and worm Wheels meshing with said worms respectively and rotatable i about parallel vertical axes, said Worm Wheels being `selectively operatively connectible to said feed operatingY member. i

25.111 a mining machine, the combination with a feed operating member adapted to cooperate dlrectly with flexible feeding means, of

motor operated driving means for said member including a fast speed transmission mechanism and a slow `speed transmission mechanism, said transmission Vmechanisms including coaxial Worms, one Worm being driven by the other through reduction gearing, and worm wheels meshing with said Worms respectively and selectively operatively connectible to said feed operating member.

26. In `a mining machine, the combination` operate directly with flexible feeding means, of

motor operateddrivingmeans for said member including a fast speed transmission mechanism and a slow speed transmission mechanism, said transmission mechanisms including coaxial worms, one worm being driven bythe other through reduction gearing, `and Worm wheels ,meshing with said Worms respectively and rotatable about parallel vertical axes, said Worm Wheels beingoperatively connectible to said feed `operating member.

e 28.11). a mining machine, the Acombination `vvith a feed operating member adapted to cooperate directly With flexible feeding means, of

motor operated driving means for said feed operating member including `fast and slow speed gear Atrains yincluding a worm, a Worm wheel driven thereby, a Worm driven by said worm Wheel, a Worm Wheel driven bysaid last mentioned Worm, a worm drivenby said last mentioned worm wheel and arranged coaxially with said irst 4mentioned Worm, and Worm Wheels meshing respectively with said first mentioned worm and said last mentioned Worm and selectively operablexas `feed operating member drivingelements- 29. In a mining machine, the combination with Aa feed operating-,f member adapted -to cooperate directly With `flexible feeding means, of

tioned Worm, aworm driven by said'last mentioned Worm Wheel andarranged coaxially with said first kmentioned Worm, and worm wheels meshing respectively with said first mentioned worm and said last mentioned worm, a gear fixed to said feed operating member, and gears driven bysaid last mentioned worm wheels respectively and meshing with said gear.

30.1n a mining machine, the combination with a feed operating member adapted to cooperate directly with'fiexible feeding means, of motor operated driving means for said feed operating member including fast and slow speed geai` trains, each gear train including, and having individual thereto, a driving element, coaxial relatively rotatable shafts, a clutch for connecting said driving element to one of said shafts, and a clutch device for connecting said other shaft to said drive shaft for rotation therewith, and connections between said other shaft and said feed operating member.

31. In a mining machine, the combination with a feed operating member adapted to c0- operate directly with fiexible feedingv means, of motor operated driving means for said feed operating member including fast and slow speed gear trains including coaxial relatively rotatable gears, gears driven by said coaxial gears respectively, gears driven by said second mentioned gears respectively, and a gear fixed to said feed operating member and meshing with said last mentioned gears respectively.

32.31 a `mining machine, the combination with a feed operating member disposed on an axis lying in a vertical plane extending longitudinally of the machine and adapted to cooperate directly with fiexible feeding means, of motor operated driving means for said feed operating member including a fast speed gear train, a slow speed gear train'driven from a gear element of said fast speed gear train, said gear trains each having a terminal gear individual thereto, said terminal gears of the two trains being relatively rotatable; and driving connections between said terminal gears respectively and said feed operating member.

33. In a mining machine, the combination with a feed operating member disposed on an axis lying in a vertical plane extending longitudinally of the machine and adapted to cooperate directly with flexible feeding means, of

motor operated driving means for said feed operating member including a fast speed gear train, a slow speed gear train driven from an element of said fast speed gear train, said gear trains including relatively rotatable gears, one in each train, and driving connections between said gears respectively and said feed operating member including a gear xed to said feed operating member and with which both of said gears mesh.

34. In a mining machine, the combination with a feed operating member rotatable about a vertical axis and adapted to cooperate directly with flexible feeding means, and motor operated driving means for said feed operating member including shafts parallel with the axis of said feed operating member, a gear fixed to said feed operating member, gears driven by said shafts respectively and meshing with said gear, a fast speed gear train for one shaft and a slow speed gear train for the other shaft.

35. In a `mining machine, the combination with a feed operating member rotatable about a vertical axis and adapted to cooperate directly with flexible feeding means, and motor operated driving means for said feed operating member including shafts parallel with the axis ofy said feed operating member, a gear xed to said feed operating member, gea 1s driven by said shafts respectively and meshing with said gear, a fast speed gear train for one shaft and a slow speed gear train for the other shaft, and clutch devices for respectively connecting said shafts in driving relation with their respective gear trains.

36.111 a mining machine, the combination with a feed operating member adapted to cooperate directly with exible feeding means, of motor operated driving means for said feed operating member including shafts rotatable about parallel axes, driving elements coaxial with said shafts respectively, friction clutches for connecting said driving element to their respective shafts, driven elements coaxial with said shafts respectively, and clutch devices for connecting said shafts to their respective driven elements for rotation together and releasable at will to permit relative rotation therebetween, and driving connections between each of said driven elements and said feed operating member.

37.111 a mining machine, the combination with 'a feed operating member adapted to cooperate directly with flexible feeding means, of motor operated driving means for said feed operating member including a fast speed transmission mechanism and a slow speed transmission mechanism, said transmission mechanisms including worms relatively rotatable at different speeds, and worm wheels rotatable about parallel vertical axes and meshing with said worms respectively, said worm wheels operatively conncctible separately in driving relation with said feed operating member.

38. In a mining machine, the combination with a feed operating member adapted to cooperate directly with fiexible feeding means, of motor operated driving means for said feed operating member including a fast speed transmission mechanism and a slow speed transmission mechanism, said transmission mechanismA including worms disposed on horizontal axes and relatively rotatable at different speeds, and worm wheels rotatable about parallel vertica axesV and meshing with said worms respectively, said worm wheels operatively connectible separately in driving relation with said feed operating member.

39. In a mining machine, the combination vwith a feedoperating member adapted to ccloperate directly with flexible feeding means, of

motor operated driving means for said feed operating member including a fast speed transmission inechanism and a slow speed transmission' mechanism, said transmission mechanisms including worms disposed on horizontal axes extending longitudinally of the machine and relatively rotatable at different speeds, and worm wheels rotatable about parallel vertical and meshing with said worms respectively, said worm wheels operatively connectible separatel;7 in driving relation with said feed operating member.

4:0. In a mining machine, the combination with a feed operating member adapted to ccoperate directly with fiexible feeding means, of motor operated driving means for said member including a fast speed transmission mechanism and a slow speed transmission mechanism, said transmission mechanisms including relatively rotatable worms, one worm driven by the other through reduction'gearing an element of which meshes with `the latter Worm, and worm wheels meshing with said worms respectively and operatively connectible separately in driving relation with said feed operating member.

fil. In a mining machine, the combination with a feed operating member adapted to cooperate directly with flexible feeding means, oi' motor operated driving means `for said member including a fast speed transmission mechanis and a slow speed transmission mechanism, transmission mechanisms including relatively rotatable worms disposed on horizontal axes, one Worm driven by the other through reductioii gearing an element of which meshes with the latter worm, and Worm Wheels meshing with said Jworms respectively and operatively connectible separately in driving relation with said feed operating member.

4 2. In a `mining machine, the combination with a feed operating member adapted to co-` operate directly with flexible feeding means, of motor operated driving means for said merober including a fast speed transmissionmech-y anism and a slow speed transmission mechzontal axes extending` longitudinally of the machine, one worm driven by the other through reduction gearing an element of which meshes `with `the latter Worm, and worm wheels meshing with said Worms respectively and operatively connectible separately in driving relation with said feed operating member.

43. In a mining machine, the combination with'a feed operating member adapted to cooperate directlywith flexible feeding means, of motor `operated driving means for said feed op erating member including fast and slow speed gear trains including a gear, a gear meshing therewithand driven thereby, a gear driven by said second mentioned gear, a gear driven by said third mentioned gear, a gear driven by said fourth mentioned gear and arranged coaxially with and rotatable relative to said first m tioned gear, and gears meshing respectivelyrivith said first mentioned gear and said fifthmentioned gear and each connectible separately from the other to drive said feed operating member.

44. In a mining machine, the combination with a feed operating member adapted to cooperate'directly with flexible feeding means, of motor operated driving means for said feed operating member including fast and slow speed gear trains including a gear, a gear meshing therewith and driven thereby, a gear driven by` said second mentioned gear, a gear driven by said third mentioned gear, a gear driven by said fourth mentioned gear and arranged coaxially with and rotatable relative to said first men-` tioned gear, gears meshing respectively with said ing intermeshing gearing, the terminal gear of one gearing rotating about an axis parallel with that of the terminal gear of theother gearing and the `axes of said terminal gears lying inthe` longitudinal Vvertical center of the machine.

46. In a mining machine, the combination with a feed operating member adapted to cofeed operating member, a driving gear coaxial with said drive shaft, a clutch for connecting said drive shaft in driving relation with said driving gear, and an interlocking clutch mechanism for connecting said shafts directly` together. K

47. In a mining machine, the combination `with a feed operatingmember adapted to c0- Yoperate directly with fiexible feeding means, and

motor operated driving means for said feed operating member including a fast speed gear train and a slow speed gear train, each gear train including, and having individual thereto, a drive shaft disposed on a vertical axis, a coaxial relatively rotatable drivenshaft, operative driving connections between said driven shaft and said feed operating member, a driving gear coaxial with said drive shaft, a clutch for connecting said vdrive shaft in driving relation with said 'driving gear, an interlocking clutch mechanism for connecting said shafts directly together, and

mechanism for controlling said clutch mechanisms operative always to connect said shafts directly together prior to the connection of said drive shaft with said driving gear.

48. In a mining machine, the combination with a feed operating member adapted to cooperate directly with dexible feeding means, of motor operated driving means for said feed operating member including a fast speed driving mechanism and a slow speed driving mechanism, each driving mechanism including a drive gear, a drive shaft coaxial therewith, a clutch for connecting said drive shaft in drivinglrelation with said drive gear, a driven shaft coaxial with and rotatable relative to said drive shaft` and interlocking clutch mechanism for connectl ing said shafts directly together, a` gear drivenv by each drivenshaft, and a gear fixed to said feed operating member and with which said last mentioned gears mesh.

49. In a l mining machine, the combination with a feed operating member adapted to cooperate directly with flexible feeding means, of motor operated driving means for said feed operating `member including a fast speed transmission mechanism and a slow speed transmission mechanism, each transmission mechanism including a shaft and said shafts being arranged` on alined axes, reduction gearing connecting one shaft in driving relation with the other shaft, worms driven by said shafts respectively, and worm Wheels meshing with said worms respectively and operatively connectible separately in driving relation with said feed operating member.

' MORRIS P. HOLMES. 

